Cleaning a Keyfit harness

Help me out here, this is all new - I've never had to clean a harness before. DD1 has a stomach of iron and never spit up much at all, much less in her car seat, but her sister is a different story.

I swear DD2 (who at least is a happy spitter) waits until she gets in her KF30 and then spits up! We may have a third baby and we expect the baby to be in the Keyfit for at least another 6 months, so I want to keep the harness reasonably clean and fresh. I don't want it or her reeking of sour breastmilk, you know? Since we're not going out at all until tomorrow, I thought I'd clean her harness this afternoon while they're napping but the manual is a little sparse and I could use some advice.

The manual says not to remove the harness or harness components, but do the neck pads on the Keyfit count as a harness component, or can I wash them like I wash the cover?

For "Cleaning Harness and LATCH Straps" it says to sponge clean using warm water and mild soap. What is considered a mild soap? I have pretty much any kind of soap one can think of but I don't want to choose something too aggressive. How wet can I let the harness get - can I dunk a sponge in warm water with a little soap and go to town, or are we talking more "damp" here?

Yes, I would put the harness covers in the wash. I would use a mild dish soap, or even baby soap or shampoo or something. I would not use a soaking wet sponge. When I cleaned mine, I used a cloth and rung it out before wiping the straps. Maybe add a bit of baking soda to the water as well to help deodorize.